000
WTPZ43 KNHC 050841
TCDEP3
 
Tropical Storm Hilda Discussion Number  23
NWS National Hurricane Center Miami FL       EP082021
200 AM PDT Thu Aug 05 2021
 
Hilda is maintaining a small, but shrinking area of deep
convection, which has rotated from the southeast to northern portion
of the storm's circulation. A 0405 UTC ASCAT-A and 0522 UTC ASCAT-B
pass had peak wind retrievals of 36 and 40 kt respectively, about
40 n mi northeast of Hilda's center. This scatterometer data
suggests that the storm might have been stronger than estimated
yesterday when the convection was more robust. However, given the
warming cloud tops and shrinking area of convection since that time,
the initial advisory intensity was kept at 35 kt, which still agrees
with the most recent subjective Dvorak estimate from TAFB.
 
Hilda is moving to the west-northwest at 8 kt as the tropical 
cyclone remains steered by a large subtropical ridge over the 
eastern North Pacific. As the storm becomes more shallow, its 
general motion should bend westward and gradually accelerate due to 
the influence of a large low-level ridge centered well northward. 
The latest track guidance is slightly more poleward early on, and 
the NHC track forecast was nudged a bit further north, but remains a 
bit south of the HFIP corrected consensus approach (HCCA). As noted 
previously, the GFS model forecast remains a northern outlier, with 
more interaction between Hilda and recently upgraded Jimena, and its 
solution is not favored at this time.
 
As Hilda continues to move over increasingly cool ocean waters and 
into a drier and more stable environment, the remaining deep 
convection will likely dissipate at some point later today. 
Additional convective bursts thereafter will become increasingly 
unlikely. The latest NHC forecast expects Hilda to weaken to a 
tropical depression later today and become a remnant low by 
tomorrow. This solution is favored by most of the intensity 
guidance. The remnant low is then forecast to open up into a trough 
by the weekend, well east of the Hawaiian Islands.
 
 
FORECAST POSITIONS AND MAX WINDS
 
INIT  05/0900Z 20.1N 129.2W   35 KT  40 MPH
 12H  05/1800Z 20.9N 130.7W   30 KT  35 MPH
 24H  06/0600Z 21.9N 132.9W   30 KT  35 MPH
 36H  06/1800Z 22.6N 135.1W   25 KT  30 MPH...POST-TROP/REMNT LOW
 48H  07/0600Z 23.2N 137.3W   20 KT  25 MPH...POST-TROP/REMNT LOW
 60H  07/1800Z...DISSIPATED
 
$$
Forecaster Papin/Beven